[autocomplete] Jumps between being expanded to the top/bottom

[foxylion]

• The issue is present in the latest release.
• I have searched the issues of this repository and believe that this is not a duplicate.

Current Behavior 😯

When having not that much space below the bottom of the input field the Autocomplete opens to the top.
By entering text into the input field the Autocomplete field gets shorter and jumps to the bottom.

Expected Behavior 🤔

After opening the Autocomplete ist should stay at the same position as the switch to the bottom is not expected and the user has to re-orientate to find the list of suggestions.

Steps to Reproduce 🕹

CodeSandbox used for reproduction: https://codesandbox.io/s/naughty-hermann-24rmn

Steps:

1. The input field
   
2. Ensure that there is not much space to the bottom
3. After clicking into the field, the Autocomplete opens to the top (as expected ✔️)
   
4. After typing an "a", the Autocomplete jumps to the bottom (not expected, should stay ❌)
   

Your Environment 🌎

Tech	Version
Material-UI	v4.11.0
React	v16.13.1
Browser	Chrome 83

[oliviertassinari]

@foxylion Interesting, do we even need the placement of the popup to maximize visibility? It feels wrong to me when the popup display on-top. I feel like this behavior is best suited for tooltips.

[joshwooding]

I’ve seen someone explicitly ask for the flipping behaviour so the popup is always visible. Seems to me popperjs is too eager when deciding whether to flip back.

[foxylion]

I would say it is expected that the drop-down is opening into the direction of "enough space". But it should not change the position while being open, as this distracts from using the auto complete input.

[oliviertassinari]

Did you look into how we could implement it?

[foxylion]

No, I'm unsure how it can be fixed. But it looks like it is an Popper.js specific behavior and could only be fixed by overriding onUpdate and preventing updates to the position. But it need to be kept in mind, that a repositioning can be required when scrolling with an expanded Autocomplete.

[pkuczynski]

I am experiencing the same issue. Did anybody found a solution for it?